Anarchists can organize and fight militarily quite effectively while still maintaining a bottom-up system, as demonstrated by the Anarchist militias of Makhno and Catalonia (and though not Anarchist, Rojava is an example of a decentralized army). The issue all Anarchist attempts have faced militarily is a lack of any allies on the world stage, allowing the authoritarian nations around them to crush them due to lack of supplies (or sudden betrayal of ML 'allies').

For anarchism to happen ideally, I believe everyone in the world has to share the same values and mindset for it to work. That foreign army invades, because they don't share the same peaceful and horizontal societial values as we do. In other words, anarchist values has to be planetary wide.

The best example of planetary wide anarchist community is the Fremen in Dune. They still have local cultural differences between the northerners and southerners but they all get along. But in spite of that condition, there is the problem yet again of foreign armies coming to invade, but from a different planet. This yet again requires the need for scaling anarchism to a universal level to prevent the threat of "outsider" invasion.

I would be an anarchist, but because of said reasons, we still don't have the culture yet of wide scale egalitarianism. Having grown up multicultural, I know many cultures are hierarchical and competitive. Unfortunately, with the current paradigm, the threat of foreign armies invading anarchist societies is real.

Maybe we should invade them first with our ideas and acts of solidarity, so that they have to focus their armed forces on quelling their local unrest.

How do you expect there to be a "we all" to invade without "us all" being able to take on nation-states?

Daily reminder that the Taliban managed to send the US military packing by fighting from a cave with a bunch of scraps. Guerilla is incredibly effective at turning empires into dust if you start the guerilla prepared, which any newly independent anarchist commune would automatically be by virtue of being newly independent.